Unique characters

Task

Given a list of strings, find characters appearing only in one string and once only.

The result should be given in alphabetical order.

Use the following list for this task:

        ["133252abcdeeffd",  "a6789798st",  "yxcdfgxcyz"]

Other tasks related to string operations:

Metrics

Counting

Remove/replace

Anagrams/Derangements/shuffling

Find/Search/Determine

Formatting

Song lyrics/poems/Mad Libs/phrases

Tokenize

Sequences

AppleScript

AppleScriptObjC

The filtering here is case sensitive, the sorting dependent on locale.

<lang applescript> use AppleScript version "2.4" -- OS X 10.10 (Yosemite) or later use framework "Foundation"

on uniqueCharacters(listOfStrings)

   set countedSet to current application's class "NSCountedSet"'s new()
   repeat with thisString in listOfStrings
       tell countedSet to addObjectsFromArray:(thisString's characters)
   end repeat
   set mutableSet to current application's class "NSMutableSet"'s setWithSet:(countedSet)
   tell countedSet to minusSet:(mutableSet)
   tell mutableSet to minusSet:(countedSet)
   set sortDescriptor to current application's class "NSSortDescriptor"'s sortDescriptorWithKey:("self") ¬
       ascending:(true) selector:("localizedStandardCompare:")
   
   return (mutableSet's sortedArrayUsingDescriptors:({sortDescriptor})) as list

end uniqueCharacters

return uniqueCharacters({"133252abcdeeffd", "a6789798st", "yxcdfgxcyz"})</lang>

Output:

Core language only

This isn't quite as fast as the ASObjC solution above, but it can be case-insensitive if required. (Simply leave out the 'considering case' statement round the call to the handler). The requirement for AppleScript 2.3.1 is just for the 'use' command which loads the "Heap Sort" script. If "Heap Sort"'s loaded differently or compiled directly into the code, this script will work on systems at least as far back as Mac OS X 10.5 (Leopard) and possibly earlier. Same output as above.

<lang applescript>use AppleScript version "2.3.1" -- OS X 10.9 (Mavericks) or later use sorter : script "Heap Sort" -- <https://www.rosettacode.org/wiki/Sorting_algorithms/Heapsort#AppleScript>

on uniqueCharacters(listOfStrings)

   script o
       property allCharacters : {}
       property uniques : {}
   end script
   
   set astid to AppleScript's text item delimiters
   set AppleScript's text item delimiters to ""
   set o's allCharacters to text items of (listOfStrings as text)
   set AppleScript's text item delimiters to astid
   
   set characterCount to (count o's allCharacters)
   tell sorter to sort(o's allCharacters, 1, characterCount)
   
   set i to 1
   set currentCharacter to beginning of o's allCharacters
   repeat with j from 2 to characterCount
       set thisCharacter to item j of o's allCharacters
       if (thisCharacter is not currentCharacter) then
           if (j - i = 1) then set end of o's uniques to currentCharacter
           set i to j
           set currentCharacter to thisCharacter
       end if
   end repeat
   if (i = j) then set end of o's uniques to currentCharacter
   
   return o's uniques

end uniqueCharacters

considering case

   return uniqueCharacters({"133252abcdeeffd", "a6789798st", "yxcdfgxcyz"})

end considering</lang>

Factor

Works with: Factor version 0.99 build 2074

<lang factor>USING: io sequences sets.extras sorting ;

{ "133252abcdeeffd" "a6789798st" "yxcdfgxcyz" } concat non-repeating natural-sort print</lang>

Output:

156bgstz

Julia

<lang julia>list = ["133252abcdeeffd", "a6789798st", "yxcdfgxcyz"]

function is_once_per_all_strings_in(a::Vector{String})

   charlist = collect(prod(a))
   counts = Dict(c => count(x -> c == x, charlist) for c in unique(charlist))
   return sort([p[1] for p in counts if p[2] == 1])

end

println(is_once_per_all_strings_in(list))

</lang>

Output:


['1', '5', '6', 'b', 'g', 's', 't', 'z']

One might think that the method above suffers from too many passes through the text with one pass per count, but with a small text length the dictionary lookup takes more time. Compare times for a single pass version:

<lang julia>function uniquein(a)

   counts = Dict{Char, Int}()
   for c in prod(list)
       counts[c] = get!(counts, c, 0) + 1
   end
   return sort([c for (c, n) in counts if n == 1])

end

println(uniquein(list))

using BenchmarkTools @btime is_once_per_all_strings_in(list) @btime uniquein(list)

</lang>

Output:


['1', '5', '6', 'b', 'g', 's', 't', 'z']

 1.740 μs (28 allocations: 3.08 KiB)
 3.763 μs (50 allocations: 3.25 KiB)

This can be rectified (see Phix entry) if we don't save the counts as we go but just exclude entries with duplicates: <lang julia>function uniquein2(a)

   s = sort(collect(prod(list)))
   l = length(s)
   return [p[2] for p in enumerate(s) if (p[1] == 1 || p[2] != s[p[1] - 1]) && (p[1] == l || p[2] != s[p[1] + 1])]

end

println(uniquein2(list))

@btime uniquein2(list)

</lang>

Output:


['1', '5', '6', 'b', 'g', 's', 't', 'z']

 1.010 μs (14 allocations: 1.05 KiB)

Perl

Translation of: Raku

<lang perl># 20210506 Perl programming solution

use strict; use warnings; use utf8; use Unicode::Collate 'sort';

my %seen; binmode(STDOUT, ':encoding(utf8)'); map { s/(\X)/$seen{$1}++/egr }

  "133252abcdeeffd", "a6789798st", "yxcdfgxcyz", "AАΑSäaoö٥🤔👨‍👩‍👧‍👧";

my $uca = Unicode::Collate->new(); print $uca->sort ( grep { $seen{$_} == 1 } keys %seen )</lang>

Output:

👨‍👩‍👧‍👧🤔15٥6AäbgoösStzΑА

Phix

function once(integer ch, i, string s)
    integer l = length(s)
    return (i=1 or ch!=s[i-1])
       and (i=l or ch!=s[i+1])
end function

sequence set = {"133252abcdeeffd","a6789798st","yxcdfgxcyz"},
         res = filter(sort(join(set,"")),once)
printf(1,"found %d unique characters: %s\n",{length(res),res})

Output:

found 8 unique characters: 156bgstz

Raku

One has to wonder where the digits 0 through 9 come in the alphabet... 🤔 For that matter, What alphabet should they be in order of? Most of these entries seem to presuppose ASCII order but that isn't specified anywhere. What to do with characters outside of ASCII (or Latin-1)? Unicode ordinal order? Or maybe DUCET Unicode collation order? It's all very vague.

<lang perl6>my @list = <133252abcdeeffd a6789798st yxcdfgxcyz>;

for @list, (@list, 'AАΑSäaoö٥🤔👨‍👩‍👧‍👧') {

   say "$_\nSemi-bogus \"Unicode natural sort\" order: ",
   .map( *.comb ).Bag.grep( *.value == 1 )».key.sort( { .unival, .NFKD[0], .fc } ).join,
   "\n        (DUCET) Unicode collation order: ",
   .map( *.comb ).Bag.grep( *.value == 1 )».key.collate.join, "\n";

}</lang>

Output:

133252abcdeeffd a6789798st yxcdfgxcyz
Semi-bogus "Unicode natural sort" order: 156bgstz
        (DUCET) Unicode collation order: 156bgstz

133252abcdeeffd a6789798st yxcdfgxcyz AАΑSäaoö٥🤔👨‍👩‍👧‍👧
Semi-bogus "Unicode natural sort" order: 15٥6ASäbgoöstzΑА👨‍👩‍👧‍👧🤔
        (DUCET) Unicode collation order: 👨‍👩‍👧‍👧🤔ä15٥6AbögosStzΑА

REXX

This REXX program doesn't assume ASCII (or any other) order. This example was run on an ASCII machine.

If this REXX program is run on an ASCII machine, it will use the ASCII order of characters, in this case,
decimal digits, uppercase Latin letters, and then lowercase Latin letters, with other characters interspersed.

On an EBCDIC machine, the order would be lowercase Latin letters, uppercase Latin letters, and then the
decimal digits, with other characters interspersed.

On an EBCDIC machine, the lowercase letters and the uppercase letters aren't contiguous. <lang rexx>/*REXX pgm finds and shows characters that are unique to only one string and once only.*/ parse arg $ /*obtain optional arguments from the CL*/ if $= | $="," then $= '133252abcdeeffd' "a6789798st" 'yxcdfgxcyz' /*use defaults.*/ if $= then do; say "***error*** no lists were specified."; exit 13; end @= /*will be a list of all unique chars. */

   do j=0  for 256;     x= d2c(j)               /*process all the possible characters. */
                        if x==' '  then iterate /*ignore blanks which are a delimiter. */
   _= pos(x, $);        if _==0    then iterate /*character not found,  then skip it.  */
   _= pos(x, $, _+1);   if _ >0    then iterate /*Character is a duplicate?  Skip it.  */
   @= @ x
   end   /*j*/                                  /*stick a fork in it,  we're all done. */

@@= space(@, 0); L= length(@@) /*elided superfluous blanks; get length*/ if @@== then @= " (none)" /*if none were found, pretty up message*/ if L==0 then L= "no" /*do the same thing for the # of chars.*/ say 'unique characters are: ' @ /*display the unique characters found. */ say say 'Found ' L " unique characters." /*display the # of unique chars found. */</lang>

output when using the default inputs:

unique characters are:   1 5 6 b g s t z

Found  8  unique characters.

Ring

<lang ring> see "working..." + nl see "Unique characters are:" + nl row = 0 str = "" cList = [] uniqueChars = ["133252abcdeeffd", "a6789798st","yxcdfgxcyz"] for n = 1 to len(uniqueChars)

   str = str + uniqueChars[n]

next for n = 1 to len(str)

   ind = count(str,str[n])
   if ind = 1
      row = row + 1
      add(cList,str[n])
   ok

next cList = sort(cList) for n = 1 to len(cList)

   see "" + cList[n] + " "

next see nl

see "Found " + row + " unique characters" + nl see "done..." + nl

func count(cString,dString)

    sum = 0
    while substr(cString,dString) > 0
          sum++
          cString = substr(cString,substr(cString,dString)+len(string(sum)))
    end
    return sum

</lang>

Output:

working...
Unique characters are:
1 5 6 b g s t z 
Found 8 unique characters
done...

Wren

Library: Wren-seq

Library: Wren-sort

<lang ecmascript>import "/seq" for Lst import "/sort" for Sort

var strings = ["133252abcdeeffd", "a6789798st","yxcdfgxcyz"] var totalChars = strings.reduce { |acc, str| acc + str }.toList var uniqueChars = Lst.individuals(totalChars).where { |l| l[1] == 1 }.map { |l| l[0] }.toList Sort.insertion(uniqueChars) System.print("Found %(uniqueChars.count) unique character(s), namely:") System.print(uniqueChars.join(" "))</lang>

Output:

Found 8 unique character(s), namely:
1 5 6 b g s t z

XPL0

<lang XPL0>int List, I, N, C; char Tbl(128), Str; string 0; [List:= ["133252abcdeeffd", "a6789798st","yxcdfgxcyz"]; for I:= 0 to 127 do Tbl(I):= 0; for N:= 0 to 2 do

       [Str:= List(N);
       I:= 0;
       loop    [C:= Str(I);
               if C = 0 then quit;
               I:= I+1;
               Tbl(C):= Tbl(C)+1;
               ];
       ];

for I:= 0 to 127 do

       if Tbl(I) = 1 then ChOut(0, I);

]</lang>

Output:

156bgstz